1 files changed, 116 insertions, 0 deletions
diff --git a/drivers/iio/common/st_sensors/st_sensors_buffer.c b/drivers/iio/common/st_sensors/st_sensors_buffer.c
new file mode 100644
index 00000000000..09b236d6ee8
--- /dev/null
+++ b/drivers/iio/common/st_sensors/st_sensors_buffer.c
@@ -0,0 +1,116 @@
+/*
+ * STMicroelectronics sensors buffer library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/interrupt.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/irqreturn.h>
+
+#include <linux/iio/common/st_sensors.h>
+
+
+int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf)
+{
+	int i, n = 0, len;
+	u8 addr[ST_SENSORS_NUMBER_DATA_CHANNELS];
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	for (i = 0; i < ST_SENSORS_NUMBER_DATA_CHANNELS; i++) {
+		if (test_bit(i, indio_dev->active_scan_mask)) {
+			addr[n] = indio_dev->channels[i].address;
+			n++;
+		}
+	}
+	switch (n) {
+	case 1:
+		len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
+			addr[0], ST_SENSORS_BYTE_FOR_CHANNEL, buf,
+			sdata->multiread_bit);
+		break;
+	case 2:
+		if ((addr[1] - addr[0]) == ST_SENSORS_BYTE_FOR_CHANNEL) {
+			len = sdata->tf->read_multiple_byte(&sdata->tb,
+					sdata->dev, addr[0],
+					ST_SENSORS_BYTE_FOR_CHANNEL*n,
+					buf, sdata->multiread_bit);
+		} else {
+			u8 rx_array[ST_SENSORS_BYTE_FOR_CHANNEL*
+				    ST_SENSORS_NUMBER_DATA_CHANNELS];
+			len = sdata->tf->read_multiple_byte(&sdata->tb,
+				sdata->dev, addr[0],
+				ST_SENSORS_BYTE_FOR_CHANNEL*
+				ST_SENSORS_NUMBER_DATA_CHANNELS,
+				rx_array, sdata->multiread_bit);
+			if (len < 0)
+				goto read_data_channels_error;
+
+			for (i = 0; i < n * ST_SENSORS_NUMBER_DATA_CHANNELS;
+									i++) {
+				if (i < n)
+					buf[i] = rx_array[i];
+				else
+					buf[i] = rx_array[n + i];
+			}
+			len = ST_SENSORS_BYTE_FOR_CHANNEL*n;
+		}
+		break;
+	case 3:
+		len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
+			addr[0], ST_SENSORS_BYTE_FOR_CHANNEL*
+			ST_SENSORS_NUMBER_DATA_CHANNELS,
+			buf, sdata->multiread_bit);
+		break;
+	default:
+		len = -EINVAL;
+		goto read_data_channels_error;
+	}
+	if (len != ST_SENSORS_BYTE_FOR_CHANNEL*n) {
+		len = -EIO;
+		goto read_data_channels_error;
+	}
+
+read_data_channels_error:
+	return len;
+}
+EXPORT_SYMBOL(st_sensors_get_buffer_element);
+
+irqreturn_t st_sensors_trigger_handler(int irq, void *p)
+{
+	int len;
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+	len = st_sensors_get_buffer_element(indio_dev, sdata->buffer_data);
+	if (len < 0)
+		goto st_sensors_get_buffer_element_error;
+
+	if (indio_dev->scan_timestamp)
+		*(s64 *)((u8 *)sdata->buffer_data +
+				ALIGN(len, sizeof(s64))) = pf->timestamp;
+
+	iio_push_to_buffers(indio_dev, sdata->buffer_data);
+
+st_sensors_get_buffer_element_error:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+EXPORT_SYMBOL(st_sensors_trigger_handler);
+
+MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST-sensors buffer");
+MODULE_LICENSE("GPL v2");